CAPNOGRAPHY In Emergency Care

1. CAPNOGRAPHYIn Emergency Care EDUCATIONAL SERIES Part 4: Non-intubated

2. Part 4: The Non-intubated Patient CAPNOGRAPHYIn Emergency Care

3. Part 4: The Non-intubated Patient Learning Objectives • List three non-intubated applications • Identify four characteristic patterns seen in • Bronchospasm • Asthma • COPD • Hypoventilation states • Hyperventilation • Low-perfusion states

4. The Non-intubated Patient CC: “trouble breathing”

5. The Non-intubated Patient CC: “trouble breathing” PE? Asthma? Emphysema? Bronchitis? Pneumonia? Cardiac ischemia? CHF?

6. The Non-intubated Patient CC: “trouble breathing” • Identifying the problem and underlying pathogenesis • Assessing the patient’s status • Anticipating sudden changes

7. The Non-intubated Patient Capnography Applications • Identify and monitor bronchospasm • Asthma • COPD • Assess and monitor • Hypoventilation states • Hyperventilation • Low-perfusion states

8. The Non-intubated Patient Capnography Applications • Capnography reflects changes in • Ventilation - movement of gases in and out of the lungs • Diffusion - exchange of gases between the air-filled alveoli and the pulmonary circulation • Perfusion - circulation of blood through the arterial and venous systems

9. The Non-intubated Patient Capnography Applications • Ventilation • Airway obstruction • Smooth muscle contraction • Bronchospasm • Airway narrowing • Uneven emptying of alveoli • Mucous plugs

10. The Non-intubated Patient Capnography Applications • Diffusion • Airway inflammation • Retained secretions • Fibrosis • Decreased compliance of alveoli walls • Chronic airway modeling (COPD) • Reversible airway disease (Asthma)

11. Capnography in Bronchospastic Conditions • Air trapped due to irregularities in airways • Uneven emptying of alveolar gas • Dilutes exhaled CO2 • Slower rise inCO2 concentration during exhalation A l v e o l i

12. C D I I A B E III Capnography in Bronchospastic Diseases • Uneven emptying of alveolar gas alters emptying on exhalation • Produces changes in ascending phase (II) with loss of the sharp upslope • Alters alveolar plateau (III) producing a “shark fin”

13. Capnography in Bronchospastic ConditionsPrevalence of Asthma • Asthma is increasing in the US • 20.3 million citizens report having asthma • Prevalence increased 75% from 1980-1994 • Two million ED visits each year • Most common chronic health problem in children • Increasing deaths due to asthma • 1987 to 1995, death rate doubled to 5600 Sources: Delbridge T., et al. 2003 Prehospital Asthma Management.Prehospital Emergency Care 7(1) 42-47 Asthmatic Statistics. American Academy of Allergies, Asthma and Immunology. http.//www.aaaai.org

14. Capnography in Bronchospastic ConditionsPathology of Asthma • Acute onset or progressive over weeks • Airway • Increased responsiveness (hyper-reactivity) • Bronchospasm • Reversible obstruction • Inflammation

15. Capnography in Bronchospastic ConditionsPathology of Asthma • Release of inflammatory mediators • Histamine, bradykinin, prostaglandins • Bronchial wall reaction • Spasm of bronchial smooth muscle • Vasodilatation with swelling of bronchial mucous membranes • Increased mucous production

16. Capnography in Bronchospastic ConditionsSymptoms of Asthma • Tachycardia • Tachypnea • Wheezing • Cough • Chest tightness • Use of accessory muscles (retractions) • Anxiety • Diaphoresis

17. Capnography in Bronchospastic ConditionsClassification of Asthma Adopted from the NIH Guidelines for the Diagnosis and Management of Asthma Source: Edmond S. D. 1998. 1997 National Asthma Education and Prevention Program Guidelines: A Practical Summary for Emergency Physicians. Annals of Emergency Medicine 31: 5: 579-594

18. Capnography in Bronchospastic ConditionsAssessment of Asthma • Symptoms and observations are primarily subjective • Severity of symptoms and your patient’s perception may not accurately reflect severity of condition More objective data needed Source: Teeter J.G., et al. 1998. “Relationship Between Airway Obstruction and Respiratory Symptoms in Adult Asthmatics. CHEST.113:5:272-277

19. Capnography in Bronchospastic ConditionsCapnogram of Asthma • 28 normal volunteers; 20 asthma patients in ED • Correlation between PEFR and slope of capnogram waveform • Conclusion • Slope value correlated with PEFR • “dCO2/dt is an effort independent, rapid noninvasive measure that indicates significant bronchospasm” Source: Yaron M. 1996. Utility of the Expiratory Capnogram in the Assessment of Bronchospasm. Annals of Emergency Medicine 28: 4

20. Capnography in Bronchospastic ConditionsCapnogram of Asthma • “expiratory airflow obstruction affects the shape of the CO2 time curve due to uneven emptying of alveolar gas.” P 312 • Waveform examples show increasing change in normal expiratory plateau with increasing obstruction (bronchospasm) Source: Hall J.B., Acute Asthma, Assessment and Management,McGraw-Hill, New York.

21. Normal Bronchospasm Capnography in Bronchospastic ConditionsCapnogram of Asthma Changes in dCO2/dt seen with increasing bronchospasm Source: Krauss B., et al. 2003. FEV1 in Restrictive Lung Disease Does Not Predict the Shape of the Capnogram. Oral presentation. Annual Meeting, American Thoracic Society, May, Seattle, WA

22. Capnography in Bronchospastic ConditionsCapnography in Asthma • Research is underway on the correlation of capnographic changes to patient’s respiratory status • Anticipating clinical trials on the impact on patient care, outcomes and healthcare costs

23. Capnography in Bronchospastic ConditionsAsthma Case Scenario • 16 year old female • C/O “having difficulty breathing” • Visible distress • History of asthma, physical exertion, “a cold” • Patient has used her “puffer” 8 times over the last two hours • Pulse 126, BP 148/86, RR 34 • Wheezing noted on expiration

24. Capnography in Bronchospastic ConditionsAsthmaCase Scenario Initial After therapy

25. Capnography in Bronchospastic ConditionsPrevalence of COPD • COPD is increasing in the U.S. • Fourth leading cause of death in adults • 16 million cases in 1996 • Increasing deaths due to COPD • 1999 estimated 110,000 • Number of deaths doubled in the past 25 years Source: Boyle, A.H. 2000. Recommendations of the National Lung Health Education Program, Heart & Lung 29: 6: 446-449

26. Capnography in Bronchospastic ConditionsPathology of COPD • Chronic, progressive disease process • Major risk factors: smoking, exposure to dusts and fumes, history of frequent respiratory infections • Spectrum of diseases • Chronic bronchitis • Emphysema • Asthma • Bronchiectisis

27. Capnography in Bronchospastic ConditionsPathology of COPD • Progressive • Partially reversible • Airways obstructed • Hyperplasia of mucous glands and smooth muscle • Excess mucous production • Some hyper-responsiveness

28. A l v e o l i Capnography in Bronchospastic ConditionsPathology of COPD • Small airways • Main sites of airway obstruction • Inflammation • Fibrosis and narrowing • Chronic damage to alveoli • Hyper-expansion due to air trapping • Impaired gas exchange

29. Capnography in Bronchospastic ConditionsSymptoms of COPD Exacerbation • Increase in chronic symptoms • SOB • Cough • Wheezing • Use of accessory muscles • Sputum - increased volume, tenacity and purulence • Anxiety • Diaphoresis • Chest tightness

30. Capnography in Bronchospastic ConditionsSymptoms of COPD Exacerbation • May also have • Fever - underlying infection • Co-morbidity • Congestive heart failure • Acute coronary syndrome • Diabetes mellitus • Hypertension

31. Capnography in Bronchospastic ConditionsAssessment of COPD • Symptoms and observations are primarily subjective • Severity of symptoms and your patient’s perception may not accurately reflect severity of condition More objective data needed

32. Capnography in Bronchospastic ConditionsCapnography in COPD • Arterial CO2 in COPD • PaCO2 increases as disease progresses • Requires frequent arterial punctures for ABGs • Correlating capnograph to patient status • Ascending phase and plateau are altered by uneven emptying of gases

33. Capnography in Bronchospastic ConditionsCOPD Case Scenario • 72 year old male • C/O difficulty breathing • History of CAD, CHF, smoking and COPD • Productive cough, recent respiratory infection • Pulse 90, BP 158/82 RR 27

34. 4 5 0 Capnography in Bronchospastic ConditionsCOPD Case Scenario Initial Capnogram A Initial Capnogram B

35. Capnography in Bronchospastic ConditionsCapnogram of CHF • 207 patients in pulmonary function lab • 61 with obstructive disease (OD); 34 with restrictive disease (RD) • Correlation of slope of exhalation plateau • C/O severe difficulty breathing (FEV1<50%) • 97% of OD had elevations >4°; 5% of RD had elevations >4° • P<0.0001 • Conclusion • Changes in shape of capnogram in OD confirmed • Changes in capnogram in RD did not occur Source: Krauss B., et al. 2003. FEV1in Restrictive Lung Disease Does Not Predict the Shape of the Capnogram. Oral presentation. Annual Meeting, American Thoracic Society, May, Seattle, WA.

36. Capnography in CHFCase Scenario • 88 year old male • C/O: Short of breath • H/O: MI X 2, on oxygen at 2 L/m • Pulse 66, BP 114/76/p, RR 36 labored and shallow, skin cool and diaphoretic, 2+ pedal edema • Initial SpO2 69%; EtCO2 17mmHG

37. 4 5 3 5 2 5 0 Capnography in CHFCase Scenario • Placed on non-rebreather mask with 100% oxygen at 15 L/m; IV diuretic and SL nitroglycerin as per local protocol • Ten minutes after treatment: SpO2 69% 99% EtCO2 17mmHG 35 mmHG Time condensed to show changes

38. Capnography in Hypoventilation States • Altered mental status • Sedation • Alcohol intoxication • Drug Ingestion • Stroke • CNS infections • Head injury • Abnormal breathing • CO2 retention • EtCO2 >50mmHg

39. 4 5 0 Capnography in Hypoventilation States • EtCO2 is above 50mmHG • Box-like waveform shape is unchanged Time condensed; actual rate is slower

40. Capnography in Hypoventilation StatesCase Scenario • Observer called 911 • 76 year old male sleeping and unresponsive on sidewalk, “gash on his head” • Known history of hypertension, EtOH intoxication • Pulse 100, BP 188/82, RR 10, SpO2 96% on room air

41. Capnography in Hypoventilation States Hypoventilation Time condensed; actual rate is slower

42. 4 5 0 Capnography in Hypoventilation States Hypoventilation Hypoventilation in shallow breathing

43. Capnography in Low Perfusion • Capnography reflects changes in • Perfusion • Pulmonary blood flow • Systemic perfusion • Cardiac output

44. Capnography in Low PerfusionCase Scenario • 57 year old male • Motor vehicle crash with injury to chest • History of atrial fib, anticoagulant • Unresponsive • Pulse 100 irregular, BP 88/p • Intubated on scene

45. Capnography in Low PerfusionCase Scenario Low EtCO2 seen in low cardiac output Ventilation controlled

46. A r t e r y V e i n O x y g e n O 2 Capnography Applicationson Non-intubated Patients • New applications now being reported • Pulmonary emboli • CHF • DKA • Bioterrorism • Others?

47. Capnography in Pulmonary EmbolusCase Scenario • 72 year old female • CC: Sharp chest pain, short of breath • History: Legs swollen and pain in right calf following flight from Alaska • Pulse 108 and regular, RR 22, BP 158/88 SpO2 95%

48. Capnography in Pulmonary EmbolusCase Scenario Strong radial pulse Low EtCO2 seen in decreased alveolar perfusion

49. Part 4: The Non-intubated Patient Summary • Identify and monitor bronchospasm • Asthma • COPD • Assess and monitor • Hypoventilation states • Hyperventilation • Low perfusion • Many others now being reported

50. Part 4: The Non-intubated Patient Ready to take capnography for a run?